Once human, yuan-ti histachii are near-mindless abominations who have been transformed into reptilian humanoids to serve their yuan-ti masters. Most often, they are found guarding yuan-ti brood chambers.

Histachii are hairless creatures. Their clothing, little more than filthy rags, hangs limply over their emaciated bodies. Their gray or yellow-green skin is tough and scaly, and smells faintly of rotting meat. They have beady, bloodshot eyes, and their forked tongues continually dart in and out of their mouths. Their dull yellow teeth are like tiny hooks, razor-sharp. Their fingernails are black and twisted, resembling the claws of a lizard.

Histachii speak in short, hissing phrases. They know the languages of yuan-ti and all snakes and snakelike creatures, as well as the languages they spoke in their original human lives.

Combat: Histachii attack any nonreptilian creature or humanoid on sight, unless their yuan-ti masters give them orders to the contrary. Unsophisticated fighters, most histachii charge directly at their opponents, attacking with their claws and teeth. To protect their yuan-ti masters, histachii will fight to the death.

Regardless of their abilities in their former lives, histachii do not wield weapons or use magic. Once per day, they can become berserk. In this state, they are so enraged that they gain a +2 bonus to their attack rolls. The berserk condition persists for 2-12 (2d6) rounds.

Unlike yuan-ti, histachii have no natural magic resistance. However, they are immune to all types of hold and charm spells.

Habitat/Society: Yuan-ti create most histachii servitors from human prisoners. They also may transform human worshippers who voluntarily agree to become histachii. Humans become histachii by drinking a distillation of yuan-ti venom mixed with certain herbs and roots. (The yuan-ti prepare this special concoction.) If a human is unwilling to drink, the yuan-ti pin their captive to the ground and pour the mixture down his throat.

Any human who drinks this mixture, whether by choice or by force, must make a saving throw vs. poison with a -4 penalty. If the saving throw fails, the victim becomes a histachii in 7-12 (1d6+6) days. If the save is successful, the victim immediately lapses into a coma; death will follow in one hour. A comatose victim can be revived with a slow poison or neutralize poison spell, presuming the spell is cast within 1 hour after the mixture has been swallowed. Human-headed yuan-ti have the ability to neutralize poison, and they may save a comatose victim themselves. It is not for the victim’s benefit. A human who fails his save after drinking the mixture may suddenly find himself alive again, only to face another flask of the mixture when the yuan-ti attempt another transformation.

Only humans can become histachii. Nonhumans who drink the yuan-ti mixture must also make a save vs. poison with a -4 penalty, however. If the save is successful, the nonhuman will be violently ill, unable to take any action for 1-4 turns. If the save throw fails, the nonhuman becomes comatose and dies in 2-5 rounds.

If a human fails his saving throw after consuming the mixture, a few desperate measures may prevent his transformation into a histachii. If neutralize poison, dispel magic, remove curse, and heal are cast on the victim, in precisely this order, the transformation process will be reversed. However, the victim will permanently lose 1 point of Intelligence. A wish or a limited wish will reverse the transformation with no loss of Intelligence. Once the transformation is complete, only a wish can restore the victim to his former self. Histachii live 20-80 (2d8×10) years after their creation. They cannot breed; histachii only can be created from human beings.

Histachii are completely submissive to their yuan-ti masters, carrying out their every order without hesitation. The servants share the lairs of their yuan-ti masters. Usually, these lairs are in ancient ruins deep in tropical jungles, but sometimes yuan-ti dwell in subterranean caverns beneath human cities. A histachii’s duties include hunting, caring for the yuan-ti’s reptile menageries, guarding prisoners, and various custodial chores. In rare moments of leisure, the servants enjoy soaking in pools of cool water.

Histachii do not collect treasure.

Ecology: Like yuan-ti, histachii are strictly carnivorous, feasting on rats, worms, and other vermin. They also eat yuan-ti leftovers.